This invention relates to a boat anchor particularly designed for holding in sand and mud. The anchor has particular utility for anchoring relatively small boats in areas where the current is relatively swift and the bottom either comprises hard, scoured sand, such as in a salt-water inlets, or where the bottom comprises mud. Ideally, an anchor such as the one described above should be relatively lightweight, inexpensive, resistent to fouling and nevertheless easy to release if fouling does occur. An anchor having all of these characteristics and nevertheless particularly useful in hard sand and mud has not previously been developed.